Interface ResultSetProvider

All Known Subinterfaces:
ResultSetProvider.Large

public interface ResultSetProvider
An implementation of this interface is returned from functions and procedures that are declared to return SET OF a complex type. This interface is appropriate when the function will be generating the returned set on the fly; if it will have a ResultSet obtained from a query, it should just return ResultSetHandle instead. Functions that return SET OF a simple type should simply return an Iterator.

For a function declared to return SETOF RECORD rather than a specific complex type known in advance, the receiver argument to assignRowValues can be queried to learn the number, names, and types of columns expected by the caller.

Author:
Thomas Hallgren
  • Nested Class Summary

    Nested Classes
    Modifier and Type Interface Description
    static interface  ResultSetProvider.Large
    Version of ResultSetProvider where the assignRowValues method accepting a long row count must be implemented, and the int version defaults to using it.
  • Method Summary

    Modifier and Type Method Description
    boolean assignRowValues​(ResultSet receiver, int currentRow)
    Older version where currentRow is limited to the range of int.
    default boolean assignRowValues​(ResultSet receiver, long currentRow)
    This method is called once for each row that should be returned from a procedure that returns a set of rows.
    void close()
    Called after the last row has returned or when the query evaluator decides that it does not need any more rows.
  • Method Details

    • assignRowValues

      default boolean assignRowValues​(ResultSet receiver, long currentRow) throws SQLException
      This method is called once for each row that should be returned from a procedure that returns a set of rows. The receiver is a SingleRowWriter instance that is used to capture the data for the row.

      If the return type is RECORD rather than a specific complex type, SQL requires a column definition list to follow any use of the function in a query. The ResultSetMetaData of receiver can be used here to learn the number, names, and types of the columns expected by the caller. (It can also be used in the case of a specific complex type, but in that case the names and types are probably already known.)

      This default implementation calls assignRowValues(ResultSet,int), or throws an SQLException with SQLState 54000 (program limit exceeded) if the row number exceeds Integer.MAX_VALUE.

      Parameters:
      receiver - Receiver of values for the given row.
      currentRow - Row number, zero on the first call, incremented by one on each subsequent call.
      Returns:
      true if a new row was provided, false if not (end of data).
      Throws:
      SQLException
    • assignRowValues

      boolean assignRowValues​(ResultSet receiver, int currentRow) throws SQLException
      Older version where currentRow is limited to the range of int.
      Throws:
      SQLException
    • close

      void close() throws SQLException
      Called after the last row has returned or when the query evaluator decides that it does not need any more rows.
      Throws:
      SQLException